Method and apparatus for the formation of plywood



T. w. DIKE 1,869,957

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD Aug. 2, 1932.

Filed Feb. 28, 1931 5 Sheets-Sheet 1 v Y A TTORNEYS.

1932. 'r. w. DlKE 1,869,957

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD Filed Feb. 28. 1931 5Sheets-Sheet 2 INVENTOR:

I M V w ATTORNEYS.

Aug. 2, 1932. w DIKE 1,869,957

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD Filed Feb. 28, 1931' 5Sheets-Sheet 3 1932. T. w. DIKE 1,869,957

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD Filed Feb. 28, 1931 5Sheets-Sheet 4 Fin; 12-

ATTORNEYS.

Aug. 2, 1932.

METHOD AND APPARATUS FOR THE FORMATION OF PLYWOOD v T. w. DIKE FiledFeb. 28, 1931 5 Sheets-Sheet 5 IN VEN TOR.

A TTORNEYS.

Patented Aug. 2, 1932 UNITED STATES PATENT OFFICE THEODORE WILLIAMSIDIKE, OF NEW WESTMINSTER, BRITISH COLUMBIA, CANADA, ASSIGNOR TO I. F.LAUCKS, INC., OF SEATTLE, WASHINGTON, A CORPORATION OF WASHINGTON METHODAND APPARATUS FOR THE FORMATION OF PLYWOOD Application filed February28, 1931. Serial No. 518,944.

This invention relates to gluing methods and apparatus, and, moreparticularly, to methods and apparatus for the formation of plywood.

The present application is, in part, a continuation in part of mycopending applications Serial No. 335,998, filed January 28, 1929,Serial No. 455,97 8, filed May 26, 1930, Serial No. 36,813, filed May28, 1930, and Serial No. 456,814, filed May 28, 1930.

An object of the invention is'to provide improved methods and apparatuswhereby plywood may be formed in a particularly expeditious andeffective manner.

A further object is to provide a method of forming plywood whereby thesame may be formed in such manner as to eliminate unnecessary time,labor and expense in the operform.

Another object is directed to the provision of apparatus particularlyadapted for performing methods such as contemplated by the invention.

Still another object is to provide apparatus whereby there may beapplied efficiently and expeditiously to materials to be glued anadhesive base in discrete particle form, and particularly in powderedform.

Another object is directed to the provision of improved apparatus forthe speedy and eflicient application of gluing materials to blanks in adesired manner.

Other objects of the invention will in part be obvious and will in partappear hereinafter. 7

The invention accordingly comprises the several steps and the relationand order of one or more of such steps with respect to each of theothers, and the apparatus embodying features of construction,combinations of elements and arrangement of parts which are adapted toeffect such steps, all as exemplified in the following detaileddisclosure, and the scope of the application of which will be indicatedin the claims.

Fig. 1a is a side view showing somewhat diagrammatically a form ofapparatus similar to that shown in Fig. 1, but showing the coating ofplies of different thicknesses;

Fig. 2 is a plan view thereof;

Fig. 3 is a side view of a form of apparatus adapted for use in theformation of multiple ply panels;

Fig. 3a exemplifies an assembly formed by apparatus such as illustratedin Fig. 3;

Fig. 4 is a side view of apparatus similar to that shown in Fig. 3;

Fig. 5 is an enlarged detail side .view partly broken away showing theexemplified apparatus for disseminating a liquid;

Fig. 6 is a sectional View along the line 6-6 of Fig. 5;

Fig. 7 is a detail plan view on an enlarged scale showing the apparatusfor disseminating a powder;

Fig. 8 is asectional view taken along the lines 8-8 in Fig. 7; v

Fig. 9 illustrates a further modified form of method and apparatuswherein powder and liquid are mixed before they reach the panel; i

Fig. 10 is a fragmentary side view illustrating still anothermodification;

Fig. 11 is a similar view illustrating a further modification;

Fig. 12 is a similar View illustrating another modification;

Fig. 13 is a view on a smaller scaleillustrating the formationof athree-ply panel by means of apparatus of the nature-shown in Figs. 11and 12;

Fig. 14 is a. plan View illustrating a method and means for controllingthe amount of adhesive supplied to plies;

Fig. 15 is a partly sectional view along the lines 1515 of Fig. 14;

Fig. 16 is a view illustrating one type of ply which may be coated inaccordance with the invention;

Fig. 17 illustrates a method and means particularly adapted to theformation of assemblies including plies as illustrated in Fig. 16;

Fig. 18 illustrates another modified form of method and apparatusembodying the invention; and

Fig. 19 illustrates a further modified form.

Ordinary commercial methods of forming plywood, moreover, have aconsiderable number of drawbacks which, while recognized for many years,are still inherent in common methods. Among thesearethe failure toattainanything approaching a uniform glue spread in practicalprocedures, the diificulties in safely handling available veneer sheets,and the practical limitations in varying procedures as required inmaking up different forms of plywood. Commonly, rotating means such asglue rolls, "or in some instances a glue brush, is utilized to apply .aliquid glue. Neither gives a uniform spread, and the glue rolls, whilesomewhat more eiiicient in this and other respects, are, in spite oftheir widespread use, far from attaining the desired results. The veneeravailable for the gluer is commonly Warped or buckled throughout itsextent, so that it is practically impossible for a rotating brush orrollto apply liquid glue uniformly. Furthermore, itis a readilybreakable product, particularly when pre-dried, which is an importantdesideratum if the escape of a large excess of glue into the body of thewood is to be restricted. The pressure which may be applied by gluerolls is accordingly limited. Indeed, there is a high proportion ofbreakage in many cases where the rolls are set no tighter than justenough to feed the plies, and the pressure limitation further militatesagainst a uniform spread. Again it is commonly found necessary to groovethe rolls. which results in a pronounced pattern in the spread. Evenwith smooth rolls the glue is deposited in a pattern rather than as acontinuous uniform film over the surface. The nature of the patternconsists of alternate hills or ridges of glue separated by valleys withthe surfaces merely wetted by a thin film of glue, and a marked excessof glue must be supplied to accomplish any material reduction of thisdeficiency. Furthermore, the veneer sheets will vary at leastfivethousandths of an inch in thickness; and usually more, and even thisvariation is sufficient to cause unevenness in spread by rolls whichwill apply a substantially even coating to paper. When plies ofdifferent thicknesses are to be glued foruse in the same panel, or insuccessive quantities of panels,

either two machines must be used or discon-' tinuous operation to allowfor adjustments must be resorted to. Moreover, because of the pressurerestrictions a change in the viscosity of the glue or a substitution ofrolls having diflerently spaced grooves is commonly necessary when achange in spread, i. e., in the amount of glue applied to a givensurface area, is desired. Indeed, accuracy of control of the spread ispractically impossible because of its dependence on the precise pressureexerted by the rolls at any adjustment, which as a practical matter willbe only roughly accurate. Ordinarily the rolls are adjusted to providean opening somewhat greater than the thickness of the veneer, and anycurvature in the veneer or variation in its thickness, or amaladjustment of the rolls increases the unevenness of the deposit, withconsequent lack of uniformity of adhesion, and when two sides of theveneer are spread, causes further variation as between the glue lines.Also, disturbance of the spread in assembly manipulations and smearingand stickiness seems .to be unavoidable in such processes.

In view of the foregoing, it will be seen there has existed for someyears a need for a continuous gluin method whereby quality productsembodying pre-cut veneer and the like may be produced in a continuousand eflicient manner. In accordance with the present invention methodsand means to this end are provided, the adhesive material, indiscrete-particle, -ordinarily powdered, form, being desirably appliedwithout contact with the surface of the plies.

With the foregoing and other ends 1' 11 View, the invention contemplatesthe provision of methods and means whereby gluing materials -may be soapplied that a plurality of wood plies or the like may be glued andassembled with a minimum amount of labor and in an expeditious manner,such assemblies being efl'ectively formed in a continuous manner wherebythe output may be increased and operating cost reduced.

More specifically, the invention contemplates the provision of improvedmethods and means whereby an adhesive material in discrete particle formmay be readily supplied at the glue line. Such adhesive material maycomprise any well known or other suitable substance which possessesadhesive properties in its normal state or which is transformed byconditions present in the press, or other bonding means, into asubstance having adhesive properties. The adhesive material may beapplied in the form of dry particles or of moist particles, and may beotherwise suitably conditioned and admixed with supplemental materials.The invention also contemplates, in certain of its aspects the provisionof im roved methods and means for supplying liquid materials at the glueline, and particularly for applying a plasticizing liquid, as in caseswhere a relatively dry adhesive base is utilized in the formation oflaminated materials from materials sufficiently dry so that moisturerequired for providing plasticization or for the formation of a bondwill not otherwise be present at the glue line.

The invention furthermore contemplates the formation of an assembly ofplies, such assembling operation taking in many instances the form ofsub-steps performed at suitable times during the procedure, andcontemplates subjecting the assembled plies to bonding operations in anysuitable manner as in a veneer press, many types of which are well knownin the art.

Pursuant to the invention, pre-cut wood plies or similar materials maybe passed successively through a zone in which a gluing material isbeing so disseminated as to contact with the surface of the plies asthey are passed along. The gluing material so disseminated may be anadhesive material either of the type requiring plasticization by wateror other plasticizing agent, or any other type of material, or may be aplasticizing agent or other addition agent, either liquid, solid or anyother suitable material, it being understood that in certain of itsbroader aspects the invention contemplates the application, eitherseparately or together, of any material or plurality of materials, thepresence of which at the glue line is desirable in the gluing of woodand the like. For example, there may be provided a disseminator for apowdered adhesive material and a disseminator for an aqueousplasticizing agent, which disseminators may be arranged in any desiredrelation in respect to the direction of movement of the conveyor. Theremay be provided means for causing plies to be coated with smallparticles of a moist glue in a pasty condition. 'A single disseminatorfor powdered adhesive material may be used in instances where one oranother of the plies to be utilized contains sufficientwater 'for theformation of the bond, or when the glue utilized is plasticizableindependently of the presence of a liquid agent. Separate conveyors maybe used and a disseminator for a powdered adhesive base may beassociated with one, and a disseminator for plasticizing agent may beassociated with the other, and plies from two conveyors may be laidtogether after each has passed through the zone of material disseminatedin proximity to its conveyor. Many other suitable variations of steps orarrangement of parts may be utilized.

For instance, in the formation of panels of the usual type having threeplies, the back plies may be passed through a suitable zone or zones ofdisseminated materials, a central ply (or core) laid on each, thepartial assemblies successively passed through a further zone or zones,and the face plies thereafter put successivelyin position, the cores andthe back plies may be passed on the same or separate conveyors throughsuitable zone or zones of disseminated material, each core laid on aback ply, and a face ply disposed on top; or the cores may be suitablycoated on both sides by being passed through suitable zones, andassemblies formed by joining the surfaces of outer plies with the coatedsurface of the cores. Theformatio-n of each assembly may, as will beseen, include a step performed before the coating of the second surfaceof the core. Other suitable adaptations of the procedure may occur whenmore than three plies are utilized in the formation of a panel.Furthermore, although it is ordinarily desirable to pass the plies mderstationary disseminating means, the series of plies may be stationaryand the disseminating means moved in a uniform manner in certaininstances. Indeed, a large number of variations of procedure is possiblewithout departing from the invention.

There are described below by way of example methods and apparatusembodying the invention and illustrative of the same.

In Figs. 1 and 2 there is shown a conveyor 20 on which there may bedisposed manually or by suitable autbmatic means a succession of blanksor plies 21, a pile of such blanks being indicated at 22 as disposed ona table 23 from which they may be successively withdrawn by hand andplaced on the conveyor. Above the conveyor is disposed a shaking screen24 containing a mass of powdered dry adhesive base which may bereplenished continuously or from time to time, as desired. The screenmay be reciprocated by any type of well known or desired means, one suchmeans being exemplifiedin Figs. 7 and 8, so as to disseminate in a zonetraversed by the conveyor a cloud of particles of the adhesive basewhich will fall on successive blanks 21 as they are carried thereunderat a uniform rate of travel by the conveyor 20. The spread, i. e., theamount of glue applied, may be readily controlled by the relationbetween the speed of the conveyor and the period of vibration of thescreen, one means to this end being hereinafter exemplified. As will bereadily appreciated, this method permits the ready control of the sizeof the particles delivered to the ply to be coated. If desired, thesmaller particles may be eliminated by the previous sifting and thelarger particles eliminated by the shaking screen 24. In the event thateither the blank coated or the blank to be applied to the coated surfacecontains sufiicient moisture for plasticizing the glue, or in the eventthat no plasticizing agent is required, all that is necessaryis to applya second blank to the coated blank. Such second blanks 25 may be takenfrom a pile 26 and put in place-successively upon coated blanks.Whereupon the plies may be pressed if a complete assembly has beenformed, or

the assembly may be suitably completed; as, for example, by passing theassembled plies 21 and 25 again under the screen 24, which, it will benoted, is suflicient-ly above the conveyor 20 to permit this, andapplying a further blank; and then pressed.

As above indicated, a desirable feature of the invention is that itpermits the coating of plies of different thicknesses by the samemechanism without adjustment. One type of procedure of this nature isindicated. in Fig. 1a, wherein there are disposed. on the conveyor 20 inalternation relatively thick core plies 21a and relatively thick backplies 216 which are carried by the conveyor under the disseminatingmeans 24. After the ,plies are suitably spread a core 21a is placed uponeach back ply 21b and a face ply 25a disposed thereupon to form athree-ply assembly, and

the assembly subjected to bonding conditions, as in a plywood press ofsuitable type.

As indicated in Fig. 3, the apparatus can be readily adapted for thequantity production of multiple ply panels by the use of a plurality ofspaced disseminating means. In this figure there is shown a conveyor 27longerthan the conveyor 20 and equipped.

with a second shaking screen 28 spaced from the shaking screen 24 so asto permit a partial assembly, formed by laying a blank 25 on the blank21, to pass under the second shak ing screen to receive a coating of anadhesive base, after which a third blank 29 may be taken from 'a piler30and laid on the blank 25. The assemblies (one o-f which is shown on anenlarged scale in Fig. 3a) will then be ready for pressing intothree-ply panels. The apparatus may be similarly modified to permit theassembly of panels composed of four, five or more plies in this or otherparticular manners.

In instances where it is desired to apply a 'plasticizing or otherliquid to the glue line, it is often desirable to similarly disseminatethe same in a zone traversed by the moving plies, instead of spreadingthe liquid directyou the wood. To this end an atomizer or other spraymeans may be provided. Among other advantages this permits a limitedamount of water to be evenly applied to the surface, and, in cases wherea plasticizing agent is applied after a dry adhesive base, permits theplasticizing liquid to be put in place without disturbing the coating ofthepowder. It is to be appreciated, however, that the plasticizing orother liquid may be applied to uncoated blanks, as well as the blanks inany of avariety of other conditions. "Fig. 4 shows a form ofconstruction gen erally similar to that shown in Fig. 3 e mbodying, inaddition to the means for disseminating a powdered adhesive base, anatomizer 31 disposed, in the present instance. beyond the shaking screen24 in the direction the application of dry particles.

of the movement of the conveyor, and a similar atomizer 32 disposedbeyond the shaking screen 28. In this instance the back 21 is movedthrough the zone in which a cloud. of

powdered adhesive base is being disseminatwater is sprayed into aconduit 36. A draft of air forced through this conduit breaks the sprayin a mist or cloud which is blown through a nozzle 37. The disseminatedliquid falls, as indicated at 38, on the surface I ofplies carried bythe conveyor 20.

The form of means for disseminating a powdered adhesive material isexemplified in greater detail in Figs. 7 and 8. The vibratory screen 24is supported for recipro cable. movement on arms 39 carried by aframe-work 40. The screen-is attached by means of a link 41 toaneccentrically mounted member 42 carried on a shaft 43 which is connectedby means including a belt 44 to a-shaft 45. In the present instance, theg shaft 45 carries wheels 46 which carry the elements of the conveyor 20by which plies are passed through the zone 24a of powdered adhesivematerial disseminated by vibratory movements of the screen. Suitablepower means (not shown) are, of course, provided 1 for driving theconveyor and the associated mechanism. i

As above set forth, the invention contemplates the application of moistparticles of adhesive material to the plies as well as Such a plicationmay be effected by suitably breaking up and disseminating a pasty massof adhesive material, or intermingling moisture with dry particleseither before or after the initial dissemination of the particles. Thereis exemplified in Fig. 9 one form of apparatus embodying this feature ofthe nvention.

In the exemplified form the construction includes a conveyor 20 and avibratory screen 24 which may be provided with associated parts, all asexemplified in the preceding figures. Adjacent the screen there isdisposed an atomizer member 47 comprising a water inlet 48. air draftconduit 49, blower 50 similar to those of the atomizers 31 and 32 andwith a nozzle 51 arranged todirect the mist of atomized liquid into thecloud of dissemlnated dry particles fallingfrom the shaking screen. Thetwo disseminated materials are accordingly mixed so that the plies '21passing through the zone of disseminated particles receive on theirupper surfaces a coating of moist particles of adhesive material. It isto be noted in this connection that the use of an air current in theapplication of a powdered material to a surface, and apparatus therefor,is disclosed and claimed in the copending application of Louis G.Merritt and Ericsson H. Merritt. Serial No. 542,257, filed June 5, 1931,wherein one particularly desirable form of disseminating means isdisclosed.

In certain instances, it is desirable that no adhesive material contactwith the conveyor elements. One form of apparatus whereby suchcontactmay be avoided as exemplified in Fig. 10, wherein the zone inwhich the adhesive material is disseminated is disposed within a spacebetween two'conveyors which the plies bridge as they are passed throughthe zone. A disseminating means 52 consisting, in the presentinstance,of a vibratory screen similar to the screen 24, for example, is disposedabove a space between the. forward end of a conveyor member 53 and therear end of a conveyor member 54, the plies utilized being of sufficientextent to bridge the gap between these two conveyors. There isexemplified at 55 a ply bridging the conveyors and receiving on itssurface a coating of disseminated material 56. There is also exemplifiedin this figure a catch-pan 57 disposed at the bottom of the zone inwhich the material not received on the surfaces of the plies may becaught for re-use. A similar catch-pan maybe utilized in connection withother types of apparatus to catch material falling around the sides ofthe conveyor, for example.

In Fig. 11 there is exemplified a similar construction wherein there areprovided bafiies 58 and 59 for the purpose of effectively preventing thedisseminated material from spreading sidewise to a point where it willfall upon one of the conveyors. The provision of such baflies isparticularly advantageous in instances wherein atomizers are employed tomix a mist with the disseminated powder and there are exemplified inFig. 11 atomizer nozzles 60 and 61 protruding through the sides of thebaffles 58 and 59, respectively.

Powdered material may be supplied to the vibratory screen or otherdisseminating means in any suitable manner. Preferably, however, it isdesirable to provide means for efi'ectuating a continuous and controlledsupply of material thereto. One such means is exemplified in Fig. 12,wherein there is provided a hopper 62 having a laterally extended bottomopening 63 through which a limited'amount of glue continuously passesonto a vibratory screen 64 from which it is disseminated into a zonetraversed by panels on a conveyor 65.

In Fig. 13 there is exemplified an arrangement embodying certain of thefeatures set forth in Figs. 11 and 12 adapted for the production of athree-ply panel. This apparatus comprises a third conveyor 66, inaddition to conveyors 53 and 54, and an additional shaking screen 67,besides the shaking screen 52. The shaking screen 67 is disposed betweenthe ends of the conveyors 54 and 66 and baffles 68 and 69 similar to thebaffles 58 and 59 are provided in connection therewith, Hoppers 50 and71 are provided above the vibratory screens 52 and 67, respectively. Aliquid from the tank 72 is conducted through the pipe 73 to pipes 74,one of which enters each of a plurality of conduits 75 leading tonozzles 60, 61, 76 and 77, respectively Each of the conduits 75 isconnected by a larger conduit 78 to a blower member 79.

It is often desirable to utilize various amounts of adhesive material inthe gluing of various types of materials, and to this end the inventioncontemplates controlling the spread by varying the amount of adhesivematerial disseminated in different instances. One means to this end isexemplified in Figs. 14 and 15 wherein the vibratory screen 80 is shownas connected to a cam member 81 carried on a shaft 82. A cone 83 isdisposed on this shaft and is connected by means of a belt 84 to anoppositely disposed cone 85 carried on a shaft 86, which is connected toa conveyor shaft 87 by means including a belt 88. A shifter 89, undercontrolof a handle 90, acts to position the belt 84 to control therelative speed of vibration of the vibratory screen and the speed ofmovement of the conveyor 91.

lVhile in certain instances it is desirable to apply first a dryadhesive base and then a plasticizing agent to the plies; in otherinstances, and particularly in the use of warped dry plies, as shown at92 in Fig. 16, it is desirable to have the surface of the plies wet sothatthe disseminated adhesive material will adhere. evenly thereto. Fig.17 shows one such arrangement wherein plies 92 are carried by a conveyor93 first under an atomizing means 94 and then under a means 95 fordisseminating a powdered adhesive material.

Another modification is exemplified in Fig. 18 wherein there areutilized two conveyors 96 and 97 having a parallel movement andeachhaving disposed above the same means for disseminating a gluingmaterial, this means consisting, in the present instance, of vibratoryscreens 98 and 99. A series of plies 100 are taken successively from atable 101 and disposed on the conveyor 96; and simultaneously a seriesof plies 102 are taken from a table 103 and disposed on the conveyor 97.After both sets of plies have passed through the zones of materialdisseminated by the respective vibratory screens, each ply 100* 1slifted from the conveyor 96 and disposed on a ply 102 on the conveyor97, whereupon a ply 104 from the table 105 is disposed on top of eachpartial assembly thus formed.

In certain cases, and particularly where different types of wood areused in the face and back plies than in the core, and also where theface and back are so thin that it is undesirable to apply a gluingmaterial directly thereto, it is desirable to apply gluing materialdirectly to both sides of the core. One type of method and means to thisend is exemplified in Fig. 19. A series of cores 106 are takensuccessively from a table 107 and placed on a conveyor 108. They arepassed successively by the conveyor through the zone of adhesivematerial disseminated by a disseminating means 109. Simultaneously aseries of back plies 110 are taken from the table 110a and placed on aconveyor 111 which moves parallel to the conveyor 108. After each one ofthe cores has received a coating on one side, it is picked up and turnedover so that its coated surface rests against the upper surface of a pl110, whereupon the partial assembly thus ormed is passed under adisseminating means 112, whereby the uncoated surface ofthe core iscoated. A face ply 113' is then taken from a table 114: and placed uponthe partial assembly, this procedure being performed successively in acontinuous manner.

In the formation of plywood panels in accordance with the invention theassembled plies are subjected to bonding conditions in any Well known orsuitable manner. For example, after the assembly is completed,regardless of the number of plies it contains, the same may be suitablydisposed and treated in a suitable press ,or other bonding mecha nism,such mechanism comprising any of the many well known means, or any othersuitable means to this end. I

It will thus be seen that there has been provided a method and meanswhereby the application of gluing materials in discrete partlcle formmay be readily accomplished, and whereby the formation of plywood maynot only be more effectively and satisfactorily accomplished, but alsowhereby plywood may be produced in a particularly efiicient andinexpensive manner, and can be produced in large quantities in arelatively small space.

Moreover, there is provided a procedure and apparatus whereby the lackof uniformity resulting from the use of prior procedures in practicalquantity production is reduced or avoided, whereby plies of differentthicknesses may be glued without interruption in continuity, whereby anylikelihood of breakage is eliminated, whereby the spread can be readilyvaried without discontinuity of operation, and whereby the handling andgluing of the rectangular pieces of precut veneer commonly available tothe gluer is greatly simplified and facilitated.

For the sake of facility of expression, the term wooden squares isutilized to describe such pieces of veneer and the like, and it is to beunderstood that this term, as used in the appended claims, is intendedto include plies of natural wood and plies of artificial sheet materialused as substitutes therefor, which plies are sufliciently short so thatthey may e readily handled without rolling or unrolling, regardless oftheir geometric shape.

Since certain changes in carrying out the above process and in theconstructions set forth, which embody the invention may be made withoutdeparting from its scope, it is intended that all matter contained inthe above description or shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and s ecific features of the invention hereindescri d, and all statements of the scope of the invention which as amatter of language might be said to fall therebetween.

Reference is hereby made to my co-pending applications Serial Nos.538,983, filed May 21, 1931, and 596,070, filed March 1, 1932. Referenceis also made to the co-pending ap plication of myself, Irving F. Laucksand Charles N. Cone, Serial No. 351,822, filed April 1, 1929.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

1. The method of assembling plywood panels which comprises passing 1n acontinu-= ous manner through a zone in which there is a controlledconcentration of the adhesive particles suspended in air the surfaces ofplies that are to receive the adhesive, and i ringing such' surfacesinto juxtaposition with the remaining plies.

2. The method of forming plywood, which comprises continuouslydisseminating a powdered adhesive material in air in a given zone,passing wooden squares one after another through said zone to receivesaid adhesive material on a surface thereof, forming assemblies eachincluding at least one of said coated squares, and subjecting theassemblies to wooden square upon the coated surface of each partialassembly, and subjecting the assemblies to bonding conditions.

4. The method of forming plywood, which comprises continuouslydisseminating a powdered adhesive material in air in a given zone,continuously disseminating a supplemental material in another zone,passing wooden squares one after another first through one of said zonesand then through the other of said zones to receive said materials on asurface thereof, forming assemblies each including at least one of saidcoated squares, and subjecting the assemblies to bonding conditions.

5. The method of forming plywood, which comprises continuouslydisseminating a powdered adhesive material in air in a given zone,continuously disseminating a liquid in another zone, passing woodensquares one after another first through one of said zones and thenthrough the other of said zones to receive said materials on a surfacethereof, forming assemblies each including at least one of said coatedsquares, and subjecting the assemblies to bonding conditions.

6. The method of forming plywood, which comprises continuouslydisseminating a powdered adhesive material in air in a given zone,continuously disseminating a plasticizing liquid in air in another zone,passing relatively dry wooden squares one after another first throughone of said zones and then through the other of said zones to receivesaid materials on a surface thereof, forming assemblies each includingat least one of said coated squares, and subjecting the assemblies tobonding conditions.

7. The method of forming plywood, which comprises continuouslydisseminating a powdered adhesive material in air in a given zone,continuously disseminating a liquid in air in another zone, passingwooden squares one after another first through the first-mentioned zoneand then through the second-mentioned zone 'to receive said materials ona surface thereof, forming assemblies each including at least one ofsaid coated squares, and subjecting the assemblies to bondingconditions.

.8. The method of forming plywood, which comprises continuouslydisseminating a liquid in air in a given zone, continuouslydisseminating a powdered adhesive material in air in another zone,passing relatively dry wooden squares one after another first throughthe first-mentioned zone and then through the second-mentioned zone toreceive said materials on a surface thereof, forming assemblies eachincluding at least one of saidcoated squares, and subjecting theassemblies to bonding conditions.

9. The method of forming plywood, which comprises continuouslydisseminating a powdered adhesive material in air in a given zone,

continuously disseminating a liquid in air in another zone, passingwooden squares one after another first through one of said zones andthen through the other of said zones to receive said materials on asurface thereof, successively forming partial assemblies each includingone of said coated squares and an additional square, continuouslydisseminating a powdered adhesive material in air in an additional zone,continuously disseminating a liquid in air in another additional zone,passing said partial assemblies first through one of said additionalzones and then through the other thereof, completing each assembly, andsubjecting the assemblies to bonding conditions.

10. The method of forming plywood, which comprisescontinuouslydisseminating a powdered adhesive material in a given zone,passing wooden squares one after another through said zone to receivesaid adhesive material on the surface thereof, similarly causing saidwooden squares to receive adhesive materials on their opposite surfaces,forming assemblies each including at least one of said coated squaresand at least two additional wooden squares and subjecting the assembliesto bonding conditions.

11. The method of forming plywood, which comprises continuouslydisseminating a powdered adhesive material in air in a given zone,passing wooden squares one after another through said zone to receivesaid adhesive material on a surface thereof, moving additional woodensquares alongside the firstmentioned squares, disposing a coated surfaceof each of the first-mentioned squares upon the upper surface of one ofthe secondmentioned squares, continuously disseminating a powderedadhesive material in a second zone, passing the previously formedpartial assemblies through said second zone with the first-mentionedsquares in position to receive said adhesive material on the surfacesthereof opposite the previously coated surfaces, successively completingsaid assemblies, and subjecting the assemblies to bonding conditions.

12. The method of forming plywood, which comprises continuouslyprojecting a cloud of moist adhesive particles in a given zone, passingcommercially dry wooden squares one after another through said zone toreceive said adhesive material on a surface thereof, forming assemblieseach including at least one of said coated squares, and subjecting theassemblies to bonding conditions. The method of forming plywood, whichcomprisescontinuously disseminating powdered adhesive material in air ina given zone, continuously directin a cloud of discrete particles of aliquid into the disseminated material to form a cloud of moistparticles, passing wooden squares one after another through said zone toreceive said adhesive material on the surface thereof, formingassemblies each including at least one of said coated squares, andsubjecting the assemblies to bonding conditions.

14. The method of forming plywood, which comprises moving relatively toeach other a series of wooden squares and mechanism for disseminating acloud of powdered adhesive material on a surface thereof, said movementbeing uniform with respect to I each of said squares, forming assemblieseach including at least one of said coated squares, and subjecting theassemblies to bonding conditions.

15. Apparatus for the formation of plywood, including conveyor meansadapted to support wooden squares and to carry the same along a path,and means to direct particles of a powdered adhesive material toward'thepath of movement of the squares, said directing means being disposedsuiticiently above said conveyer means to permit wooden squares ofvarious heights to be moved thereunder.

:16. Apparatus for the formation of plywood, including conveyor meansadapted to support wooden squares and to carry the same along a path,means to direct particles of a powdered adhesive material toward thepath of movement of the squares, said direct-- wooden squares.

ing. means being disposed sufliciently above said conveyor means topermit wooden squares of various heights to be moved thereunder, andmeans to vary the relative speed of the conveyor and the action by thedirecting means to regulate the amount of powdered adhesive materialreceived by the 17. Apparatus for the formation of plywood, includingconveyormeans adapted to support wooden squares and to carry the samealong a path, means to direct particles of a powdered adhesive materialtoward the path of movement of the squares, and means to directparticles of a liquid toward the path of movement of the squares, eachof said directing means being disposed sufiicientlyabove said conveyormeans to permit wooden squares of various heights to be movedthereunder.

18. Apparatus for the formation of plywood, including conveyor meansadapted to support Wooden squares and to carry the same along a path,means to direct particles of a powdered adhesive material toward thepath of movement of the squares, and means to comingle particles of aliquid with the disseminated powder before the latter reaches said path,said directing and comingling means being disposed sufficiently abovesaid conveyor means to permit wooden squares of various heights toreceive said comingled particles.

19. Apparatus for the formation of plywod, including conveyor meansadapted to along a path, and means to direct particles of a powderedadhesive material toward a portion of said path, said conveyor meansin-' cluding a pair of aligned conveyor elements sufficiently spaced toleave a gap therebetween at the aforesaid portion of said path andsufficiently close together so that the squares will bridge said gap.

20: Apparatus for the formation of plywood, including conveyor meansadapted to support wooden squares and to carry the same along a path,means to direct particles of a powdered adhesive material toward aportion of said path, said conveyor means including a pair of alignedconveyor elements sufficiently spaced to leave a gap therebetween at theaforesaid portion of said path and sufliciently close together so thatthe squares Will bridge said gap, and battle means for preventing thedisseminated material from reaching either of said conveyor elements.

21. Apparatus for the formation of plywood, including conveyor meansadapted to support wooden squares and to carry the same along a path,means to direct particles of a powdered adhesive material toward thepath of movement of the squares, said directing means being disposedsufficiently above said conveyor means to permit Wooden squares ofvarious heights to be moved thereunder, said directing means comprisinga vibratory member, and means continuously to supply a controlledflow-of powdered adhesive material to said vibratory member.

In testimony whereof I affix my signature.

THEODORE WILLIAMS DIKE.

